string.upper() not working correctly with umlauts

Other
#1

string.upper(‘müller’) returns MüLLER

But the correct and awaited response should be

MÜLLER

Does anybody know how to fix this ?

I don’t want to preformat all my text/headlines in uppercase

Thanks in advance

pp

#2

I would suggest that it is because lua strings only handle the standard 32-127 character set. You may have to break it down into unicode characters and reassemble it. The good thing that in the first 256 characters http://en.wikipedia.org/wiki/C1_Controls_and_Latin-1_Supplement it is easy to capitalise 

#3

I would suggest that it is because lua strings only handle the standard 32-127 character set. You may have to break it down into unicode characters and reassemble it. The good thing that in the first 256 characters http://en.wikipedia.org/wiki/C1_Controls_and_Latin-1_Supplement it is easy to capitalise